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Commit 5d77c1ea authored by Matthieu Schaller's avatar Matthieu Schaller
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Revert "Merge branch 'cosmological_integration' into 'master'" 

This reverts commit 28265917, reversing
changes made to 856bcb95.
parent b70c7ac4
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......@@ -113,7 +113,6 @@ tests/testSelectOutput
tests/testReading
tests/testSingle
tests/testTimeIntegration
tests/testIntegration
tests/testSPHStep
tests/testKernel
tests/testKernelGrav
......
src/cosmology.c
+ 140
− 187
View file @ 5d77c1ea
......@@ -48,51 +48,35 @@ const int cosmology_table_length = 10000;
#ifdef HAVE_LIBGSL
/*! Size of the GSL workspace */
const size_t GSL_workspace_size = 100000;
/* GSL interpolator object */
gsl_interp *poly;
/* GSL interpolation accelarator object */
gsl_interp_accel *acc;
#endif
/**
* @brief Returns the interpolated value from a table.
*
* Uses GSL's cubic interpolation.
* Uses linear interpolation.
*
* @param y_table The table of value to interpolate to (should be of length
* cosmology_table_length).
* @param x_table The table of value to interpolate from (should be of length
* @brief table The table of value to interpolate from (should be of length
* cosmology_table_length).
* @param x The value to interpolate at.
* @param x_min The mininum of the range of x.
* @param x_max The maximum of the range of x.
* @brief x The value to interpolate at.
* @brief x_min The mininum of the range of x.
* @brief x_max The maximum of the range of x.
*/
static INLINE double interp_table(const double *restrict y_table,
const double *restrict x_table,
const double x, const double x_min,
const double x_max) {
static INLINE double interp_table(const double *table, const double x,
const double x_min, const double x_max) {
/* Recover the range of interest in the log-a tabel */
const double delta_x = ((double)cosmology_table_length) / (x_max - x_min);
const double xx = (x - x_min) * delta_x;
const int ii = (int)xx;
const double xx =
((x - x_min) / (x_max - x_min)) * ((double)cosmology_table_length);
#ifdef SWIFT_DEBUG_CHECKS
if (ii <= 1) error("Wrong ii - too small!");
if (ii >= cosmology_table_length - 1) error("Wrong ii - too large!");
if (x < x_table[ii - 2] || x > x_table[ii + 1])
error("Extrapolating not interpolating!");
#endif
const int i = (int)xx;
const int ii = min(cosmology_table_length - 1, i);
/* Initialise the interpolation range with 4 data points
* The point of interest is in the range [ii - 1, ii] */
// gsl_interp_init(poly, &x_table[ii - 2], &y_table[ii - 2], 4);
/* Indicate that the whole array is aligned on boundaries */
swift_align_information(double, table, SWIFT_STRUCT_ALIGNMENT);
/* Interpolate! */
// return gsl_interp_eval(poly, &x_table[ii - 2], &y_table[ii - 2], x, acc);
return y_table[ii - 1] + (y_table[ii] - y_table[ii - 1]) * (xx - ii);
if (ii <= 1)
return table[0] * xx;
else
return table[ii - 1] + (table[ii] - table[ii - 1]) * (xx - ii);
}
/**
......@@ -151,6 +135,26 @@ __attribute__((const)) static INLINE double E(
Omega_l * exp(3. * w_tilde(a, w0, wa))); /* Lambda */
}
/**
* @brief Returns the time (in internal units) since Big Bang at a given
* scale-factor.
*
* @param c The current #cosmology.
* @param a Scale-factor of interest.
*/
double cosmology_get_time_since_big_bang(const struct cosmology *c, double a) {
#ifdef SWIFT_DEBUG_CHECKS
if (a < c->a_begin) error("Error a can't be smaller than a_begin");
#endif
/* Time between a_begin and a */
const double delta_t =
interp_table(c->time_interp_table, log(a), c->log_a_begin, c->log_a_end);
return c->time_interp_table_offset + delta_t;
}
/**
* @brief Update the cosmological parameters to the current simulation time.
*
......@@ -159,7 +163,7 @@ __attribute__((const)) static INLINE double E(
* @param ti_current The current (integer) time.
*/
void cosmology_update(struct cosmology *c, const struct phys_const *phys_const,
const integertime_t ti_current) {
integertime_t ti_current) {
/* Save the previous state */
c->z_old = c->z;
......@@ -352,24 +356,10 @@ void cosmology_init_tables(struct cosmology *c) {
#ifdef HAVE_LIBGSL
/* We want to extend the tables on both sides so that we never
have to worry about edges when interpolating */
const double fac = 1. + 16. / ((double)cosmology_table_length);
const double a_begin = c->a_begin / fac;
const double a_end = c->a_end * fac;
c->log_a_table_begin = log(a_begin);
c->log_a_table_end = log(a_end);
/* Allocate the GSL interpolator memory */
const gsl_interp_type *t = gsl_interp_polynomial;
acc = gsl_interp_accel_alloc();
poly = gsl_interp_alloc(t, 4);
/* Retrieve some constants */
const double a_begin = c->a_begin;
/* Allocate memory for the interpolation tables */
if (swift_memalign("cosmo.table", (void **)&c->log_a_interp_table,
SWIFT_STRUCT_ALIGNMENT,
cosmology_table_length * sizeof(double)) != 0)
error("Failed to allocate cosmology interpolation table");
if (swift_memalign("cosmo.table", (void **)&c->drift_fac_interp_table,
SWIFT_STRUCT_ALIGNMENT,
cosmology_table_length * sizeof(double)) != 0)
......@@ -390,17 +380,18 @@ void cosmology_init_tables(struct cosmology *c) {
SWIFT_STRUCT_ALIGNMENT,
cosmology_table_length * sizeof(double)) != 0)
error("Failed to allocate cosmology interpolation table");
if (swift_memalign("cosmo.table", (void **)&c->scale_factor_interp_table,
SWIFT_STRUCT_ALIGNMENT,
cosmology_table_length * sizeof(double)) != 0)
error("Failed to allocate cosmology interpolation table");
/* Prepare a table of scale factors for the integral bounds */
const double delta_a =
(c->log_a_table_end - c->log_a_table_begin) / cosmology_table_length;
(c->log_a_end - c->log_a_begin) / cosmology_table_length;
double *a_table = (double *)swift_malloc(
"cosmo.table", cosmology_table_length * sizeof(double));
for (int i = 0; i < cosmology_table_length; i++) {
a_table[i] = exp(c->log_a_table_begin + delta_a * (i + 1));
c->log_a_interp_table[i] = log(a_table[i]);
}
for (int i = 0; i < cosmology_table_length; i++)
a_table[i] = exp(c->log_a_begin + delta_a * (i + 1));
/* Initalise the GSL workspace */
gsl_integration_workspace *space =
......@@ -448,16 +439,21 @@ void cosmology_init_tables(struct cosmology *c) {
c->hydro_kick_corr_interp_table[i] = result;
}
/* Integrate the time \int_{0}^{a_table[i]} dt */
/* Integrate the time \int_{a_begin}^{a_table[i]} dt */
F.function = &time_integrand;
for (int i = 0; i < cosmology_table_length; i++) {
gsl_integration_qag(&F, 0., a_table[i], 0, 1.0e-13, GSL_workspace_size,
gsl_integration_qag(&F, a_begin, a_table[i], 0, 1.0e-10, GSL_workspace_size,
GSL_INTEG_GAUSS61, space, &result, &abserr);
/* Store result */
c->time_interp_table[i] = result;
}
/* Integrate the time \int_{0}^{a_begin} dt */
gsl_integration_qag(&F, 0., a_begin, 0, 1.0e-10, GSL_workspace_size,
GSL_INTEG_GAUSS61, space, &result, &abserr);
c->time_interp_table_offset = result;
/* Integrate the time \int_{0}^{1} dt */
gsl_integration_qag(&F, 0., 1, 0, 1.0e-13, GSL_workspace_size,
GSL_INTEG_GAUSS61, space, &result, &abserr);
......@@ -467,6 +463,41 @@ void cosmology_init_tables(struct cosmology *c) {
c->time_begin = cosmology_get_time_since_big_bang(c, c->a_begin);
c->time_end = cosmology_get_time_since_big_bang(c, c->a_end);
/*
* Inverse t(a)
*/
const double delta_t = (c->time_end - c->time_begin) / cosmology_table_length;
/* index in the time_interp_table */
int i_a = 0;
for (int i_time = 0; i_time < cosmology_table_length; i_time++) {
/* Current time
* time_interp_table = \int_a_begin^a => no need of time_begin */
double time_interp = delta_t * (i_time + 1);
/* Find next time in time_interp_table */
while (i_a < cosmology_table_length &&
c->time_interp_table[i_a] <= time_interp) {
i_a++;
}
/* Find linear interpolation scaling */
double scale = 0;
if (i_a != cosmology_table_length) {
scale = time_interp - c->time_interp_table[i_a - 1];
scale /= c->time_interp_table[i_a] - c->time_interp_table[i_a - 1];
}
scale += i_a;
/* Compute interpolated scale factor */
double log_a = c->log_a_begin + scale * (c->log_a_end - c->log_a_begin) /
cosmology_table_length;
c->scale_factor_interp_table[i_time] = exp(log_a) - c->a_begin;
}
/* Free the workspace and temp array */
gsl_integration_workspace_free(space);
swift_free("cosmo.table", a_table);
......@@ -536,9 +567,10 @@ void cosmology_init(struct swift_params *params, const struct unit_system *us,
c->grav_kick_fac_interp_table = NULL;
c->hydro_kick_fac_interp_table = NULL;
c->time_interp_table = NULL;
c->time_interp_table_offset = 0.;
cosmology_init_tables(c);
/* Set remaining variables to valid values */
/* Set remaining variables to alid values */
cosmology_update(c, phys_const, 0);
/* Update the times */
......@@ -573,10 +605,6 @@ void cosmology_init_no_cosmo(struct cosmology *c) {
c->a_end = 1.;
c->log_a_begin = 0.;
c->log_a_end = 0.;
c->log_a_table_begin = 0.;
c->log_a_table_end = 0.;
c->time_base = 0.;
c->time_base_inv = 0.;
c->H = 0.;
c->H0 = 0.;
......@@ -615,6 +643,8 @@ void cosmology_init_no_cosmo(struct cosmology *c) {
c->hydro_kick_fac_interp_table = NULL;
c->hydro_kick_corr_interp_table = NULL;
c->time_interp_table = NULL;
c->time_interp_table_offset = 0.;
c->scale_factor_interp_table = NULL;
c->time_begin = 0.;
c->time_end = 0.;
......@@ -644,17 +674,13 @@ double cosmology_get_drift_factor(const struct cosmology *c,
if (ti_end < ti_start) error("ti_end must be >= ti_start");
#endif
// if (ti_start == ti_end) return 0.;
const double log_a_start = c->log_a_begin + ti_start * c->time_base;
const double log_a_end = c->log_a_begin + ti_end * c->time_base;
const double a_start = c->log_a_begin + ti_start * c->time_base;
const double a_end = c->log_a_begin + ti_end * c->time_base;
const double int_start =
interp_table(c->drift_fac_interp_table, c->log_a_interp_table,
log_a_start, c->log_a_table_begin, c->log_a_table_end);
const double int_end =
interp_table(c->drift_fac_interp_table, c->log_a_interp_table, log_a_end,
c->log_a_table_begin, c->log_a_table_end);
const double int_start = interp_table(c->drift_fac_interp_table, a_start,
c->log_a_begin, c->log_a_end);
const double int_end = interp_table(c->drift_fac_interp_table, a_end,
c->log_a_begin, c->log_a_end);
return int_end - int_start;
}
......@@ -676,17 +702,13 @@ double cosmology_get_grav_kick_factor(const struct cosmology *c,
if (ti_end < ti_start) error("ti_end must be >= ti_start");
#endif
// if (ti_start == ti_end) return 0.;
const double a_start = c->log_a_begin + ti_start * c->time_base;
const double a_end = c->log_a_begin + ti_end * c->time_base;
const double log_a_start = c->log_a_begin + ti_start * c->time_base;
const double log_a_end = c->log_a_begin + ti_end * c->time_base;
const double int_start =
interp_table(c->grav_kick_fac_interp_table, c->log_a_interp_table,
log_a_start, c->log_a_table_begin, c->log_a_table_end);
const double int_end =
interp_table(c->grav_kick_fac_interp_table, c->log_a_interp_table,
log_a_end, c->log_a_table_begin, c->log_a_table_end);
const double int_start = interp_table(c->grav_kick_fac_interp_table, a_start,
c->log_a_begin, c->log_a_end);
const double int_end = interp_table(c->grav_kick_fac_interp_table, a_end,
c->log_a_begin, c->log_a_end);
return int_end - int_start;
}
......@@ -709,17 +731,13 @@ double cosmology_get_hydro_kick_factor(const struct cosmology *c,
if (ti_end < ti_start) error("ti_end must be >= ti_start");
#endif
// if (ti_start == ti_end) return 0.;
const double log_a_start = c->log_a_begin + ti_start * c->time_base;
const double log_a_end = c->log_a_begin + ti_end * c->time_base;
const double a_start = c->log_a_begin + ti_start * c->time_base;
const double a_end = c->log_a_begin + ti_end * c->time_base;
const double int_start =
interp_table(c->hydro_kick_fac_interp_table, c->log_a_interp_table,
log_a_start, c->log_a_table_begin, c->log_a_table_end);
const double int_end =
interp_table(c->hydro_kick_fac_interp_table, c->log_a_interp_table,
log_a_end, c->log_a_table_begin, c->log_a_table_end);
const double int_start = interp_table(c->hydro_kick_fac_interp_table, a_start,
c->log_a_begin, c->log_a_end);
const double int_end = interp_table(c->hydro_kick_fac_interp_table, a_end,
c->log_a_begin, c->log_a_end);
return int_end - int_start;
}
......@@ -742,17 +760,13 @@ double cosmology_get_corr_kick_factor(const struct cosmology *c,
if (ti_end < ti_start) error("ti_end must be >= ti_start");
#endif
// if (ti_start == ti_end) return 0.;
const double a_start = c->log_a_begin + ti_start * c->time_base;
const double a_end = c->log_a_begin + ti_end * c->time_base;
const double log_a_start = c->log_a_begin + ti_start * c->time_base;
const double log_a_end = c->log_a_begin + ti_end * c->time_base;
const double int_start =
interp_table(c->hydro_kick_corr_interp_table, c->log_a_interp_table,
log_a_start, c->log_a_table_begin, c->log_a_table_end);
const double int_end =
interp_table(c->hydro_kick_corr_interp_table, c->log_a_interp_table,
log_a_end, c->log_a_table_begin, c->log_a_table_end);
const double int_start = interp_table(c->hydro_kick_corr_interp_table,
a_start, c->log_a_begin, c->log_a_end);
const double int_end = interp_table(c->hydro_kick_corr_interp_table, a_end,
c->log_a_begin, c->log_a_end);
return int_end - int_start;
}
......@@ -775,42 +789,17 @@ double cosmology_get_therm_kick_factor(const struct cosmology *c,
if (ti_end < ti_start) error("ti_end must be >= ti_start");
#endif
// if (ti_start == ti_end) return 0.;
const double log_a_start = c->log_a_begin + ti_start * c->time_base;
const double log_a_end = c->log_a_begin + ti_end * c->time_base;
const double a_start = c->log_a_begin + ti_start * c->time_base;
const double a_end = c->log_a_begin + ti_end * c->time_base;
const double int_start =
interp_table(c->drift_fac_interp_table, c->log_a_interp_table,
log_a_start, c->log_a_table_begin, c->log_a_table_end);
const double int_end =
interp_table(c->drift_fac_interp_table, c->log_a_interp_table, log_a_end,
c->log_a_table_begin, c->log_a_table_end);
const double int_start = interp_table(c->drift_fac_interp_table, a_start,
c->log_a_begin, c->log_a_end);
const double int_end = interp_table(c->drift_fac_interp_table, a_end,
c->log_a_begin, c->log_a_end);
return int_end - int_start;
}
/**
* @brief Returns the time (in internal units) since Big Bang at a given
* scale-factor.
*
* @param c The current #cosmology.
* @param a Scale-factor of interest.
*/
double cosmology_get_time_since_big_bang(const struct cosmology *c, double a) {
#ifdef SWIFT_DEBUG_CHECKS
if (a < c->a_begin) error("Error a can't be smaller than a_begin");
#endif
/* Time between a_begin and a */
const double delta_t =
interp_table(c->time_interp_table, c->log_a_interp_table, log(a),
c->log_a_table_begin, c->log_a_table_end);
return delta_t;
}
/**
* @brief Compute the cosmic time (in internal units) between two points
* on the integer time line.
......@@ -827,20 +816,16 @@ double cosmology_get_delta_time(const struct cosmology *c,
if (ti_end < ti_start) error("ti_end must be >= ti_start");
#endif
// if (ti_start == ti_end) return 0.;
const double log_a_start = c->log_a_begin + ti_start * c->time_base;
const double log_a_end = c->log_a_begin + ti_end * c->time_base;
/* Time between a_begin and a_start */
const double t1 =
interp_table(c->time_interp_table, c->log_a_interp_table, log_a_start,
c->log_a_table_begin, c->log_a_table_end);
const double t1 = interp_table(c->time_interp_table, log_a_start,
c->log_a_begin, c->log_a_end);
/* Time between a_begin and a_end */
const double t2 =
interp_table(c->time_interp_table, c->log_a_interp_table, log_a_end,
c->log_a_table_begin, c->log_a_table_end);
const double t2 = interp_table(c->time_interp_table, log_a_end,
c->log_a_begin, c->log_a_end);
return t2 - t1;
}
......@@ -863,18 +848,16 @@ double cosmology_get_delta_time_from_scale_factors(const struct cosmology *c,
error("Error a_start can't be smaller than a_begin");
#endif
const double log_a_table_start = log(a_start);
const double log_a_table_end = log(a_end);
const double log_a_start = log(a_start);
const double log_a_end = log(a_end);
/* Time between a_begin and a_start */
const double t1 =
interp_table(c->time_interp_table, c->log_a_interp_table,
log_a_table_start, c->log_a_table_begin, c->log_a_table_end);
const double t1 = interp_table(c->time_interp_table, log_a_start,
c->log_a_begin, c->log_a_end);
/* Time between a_begin and a_end */
const double t2 =
interp_table(c->time_interp_table, c->log_a_interp_table, log_a_table_end,
c->log_a_table_begin, c->log_a_table_end);
const double t2 = interp_table(c->time_interp_table, log_a_end,
c->log_a_begin, c->log_a_end);
return t2 - t1;
}
......@@ -882,43 +865,16 @@ double cosmology_get_delta_time_from_scale_factors(const struct cosmology *c,
/**
* @brief Compute scale factor from time since big bang (in internal units).
*
* This function is inefficient as it needs to search the cosmology table
* and then interpolate. A relative accuracy of <10^-6 is achieved for all
* reasonable cosmologies.
*
* @param c The current #cosmology.
* @param t time since the big bang
* @return The scale factor.
*/
double cosmology_get_scale_factor_from_time(const struct cosmology *c,
const double t) {
/* Use a bisection search on the whole table to find the
interval where the time lies */
int i_min = 0;
int i_max = cosmology_table_length - 1;
int i = -1;
while (i_max - i_min > 1) {
i = (i_max + i_min) / 2;
if (c->time_interp_table[i] > t) {
i_max = i;
} else {
i_min = i;
}
}
/* Now that we have bounds, interpolate linearly
in the log-a table */
const double delta = (t - c->time_interp_table[i]) /
(c->time_interp_table[i + 1] - c->time_interp_table[i]);
const double log_a =
c->log_a_interp_table[i] +
delta * (c->log_a_interp_table[i + 1] - c->log_a_interp_table[i]);
/* Undo the log */
return exp(log_a);
double cosmology_get_scale_factor(const struct cosmology *c, double t) {
/* scale factor between time_begin and t */
const double a =
interp_table(c->scale_factor_interp_table, t, c->time_interp_table_offset,
c->universe_age_at_present_day);
return a + c->a_begin;
}
/**
......@@ -938,15 +894,12 @@ void cosmology_print(const struct cosmology *c) {
void cosmology_clean(struct cosmology *c) {
gsl_interp_accel_free(acc);
gsl_interp_free(poly);
swift_free("cosmo.table", c->log_a_interp_table);
swift_free("cosmo.table", c->drift_fac_interp_table);
swift_free("cosmo.table", c->grav_kick_fac_interp_table);
swift_free("cosmo.table", c->hydro_kick_fac_interp_table);
swift_free("cosmo.table", c->hydro_kick_corr_interp_table);
swift_free("cosmo.table", c->time_interp_table);
swift_free("cosmo.table", c->scale_factor_interp_table);
}
#ifdef HAVE_HDF5
......
src/cosmology.h
+ 8
− 14
View file @ 5d77c1ea
......@@ -163,15 +163,6 @@ struct cosmology {
/*! Log of final expansion factor */
double log_a_end;
/*! Log of starting expansion factor of the interpolation tables */
double log_a_table_begin;
/*! Log of final expansion factor of the interpolation tables */
double log_a_table_end;
/*! Scale-factor interpolation table */
double *log_a_interp_table;
/*! Drift factor interpolation table */
double *drift_fac_interp_table;
......@@ -184,9 +175,15 @@ struct cosmology {
/*! Kick factor (hydro correction) interpolation table (GIZMO-MFV only) */
double *hydro_kick_corr_interp_table;
/*! Time since Big Bang interpolation table */
/*! Time interpolation table */
double *time_interp_table;
/*! Scale factor interpolation table */
double *scale_factor_interp_table;
/*! Time between Big Bang and first entry in the table */
double time_interp_table_offset;
/*! Time at the present-day (a=1) */
double universe_age_at_present_day;
};
......@@ -194,8 +191,6 @@ struct cosmology {
void cosmology_update(struct cosmology *c, const struct phys_const *phys_const,
integertime_t ti_current);
double cosmology_get_scale_factor(const struct cosmology *cosmo,
integertime_t ti);
double cosmology_get_drift_factor(const struct cosmology *cosmo,
const integertime_t ti_start,
const integertime_t ti_end);
......@@ -219,8 +214,7 @@ double cosmology_get_delta_time_from_scale_factors(const struct cosmology *c,
const double a_start,
const double a_end);
double cosmology_get_scale_factor_from_time(const struct cosmology *cosmo,
double t);
double cosmology_get_scale_factor(const struct cosmology *cosmo, double t);
double cosmology_get_time_since_big_bang(const struct cosmology *c, double a);
void cosmology_init(struct swift_params *params, const struct unit_system *us,
......
src/outputlist.c
+ 1
− 1
View file @ 5d77c1ea
......@@ -106,7 +106,7 @@ void output_list_read_file(struct output_list *outputlist, const char *filename,
if (type == OUTPUT_LIST_REDSHIFT) *time = 1. / (1. + *time);
if (cosmo && type == OUTPUT_LIST_AGE)
*time = cosmology_get_scale_factor_from_time(cosmo, *time);
*time = cosmology_get_scale_factor(cosmo, *time);
/* Update size */
ind += 1;
......
tests/Makefile.am
+ 2
− 4
View file @ 5d77c1ea
......@@ -28,7 +28,7 @@ TESTS = testGreetings testMaths testReading.sh testKernel \
testVoronoi1D testVoronoi2D testVoronoi3D testGravityDerivatives \
testPeriodicBC.sh testPeriodicBCPerturbed.sh testPotentialSelf \
testPotentialPair testEOS testUtilities testSelectOutput.sh \
testCbrt testCosmology testIntegration testOutputList testFormat.sh \
testCbrt testCosmology testOutputList testFormat.sh \
test27cellsStars.sh test27cellsStarsPerturbed.sh testHydroMPIrules
# List of test programs to compile
......@@ -40,7 +40,7 @@ check_PROGRAMS = testGreetings testReading testTimeIntegration \
testRiemannHLLC testMatrixInversion testDump testLogger \
testVoronoi1D testVoronoi2D testVoronoi3D testPeriodicBC \
testGravityDerivatives testPotentialSelf testPotentialPair testEOS testUtilities \
testSelectOutput testCbrt testIntegration testCosmology testOutputList test27cellsStars \
testSelectOutput testCbrt testCosmology testOutputList test27cellsStars \
test27cellsStars_subset testCooling testComovingCooling testFeedback testHashmap testHydroMPIrules
# Rebuild tests when SWIFT is updated.
......@@ -59,8 +59,6 @@ testReading_SOURCES = testReading.c
testSelectOutput_SOURCES = testSelectOutput.c
testIntegration_SOURCES = testIntegration.c
testCosmology_SOURCES = testCosmology.c
testOutputList_SOURCES = testOutputList.c
......
tests/testCosmology.c
+ 9
− 23
View file @ 5d77c1ea
......@@ -20,15 +20,11 @@
/* Some standard headers. */
#include "../config.h"
/* Some standard headers */
#include <fenv.h>
#include <math.h>
/* Includes. */
#include "swift.h"
#define N_CHECK 200
#define TOLERANCE 1e-6
#define N_CHECK 20
#define TOLERANCE 1e-7
void test_params_init(struct swift_params *params) {
parser_init("", params);
......@@ -36,21 +32,12 @@ void test_params_init(struct swift_params *params) {
parser_set_param(params, "Cosmology:Omega_lambda:0.6910");
parser_set_param(params, "Cosmology:Omega_b:0.0486");
parser_set_param(params, "Cosmology:h:0.6774");
parser_set_param(params, "Cosmology:a_begin:0.01");
parser_set_param(params, "Cosmology:a_begin:0.1");
parser_set_param(params, "Cosmology:a_end:1.0");
}
int main(int argc, char *argv[]) {
/* Initialize CPU frequency, this also starts time. */
unsigned long long cpufreq = 0;
clocks_set_cpufreq(cpufreq);
/* Choke on FP-exceptions */
#ifdef HAVE_FE_ENABLE_EXCEPT
feenableexcept(FE_DIVBYZERO | FE_INVALID | FE_OVERFLOW);
#endif
message("Initialization...");
/* pseudo initialization of params */
......@@ -72,16 +59,15 @@ int main(int argc, char *argv[]) {
message("Start checking computation...");
for (int i = 0; i < N_CHECK; i++) {
double a = 0.01 + 0.99 * i / (N_CHECK - 1.);
double a = 0.1 + 0.9 * i / (N_CHECK - 1.);
/* Compute a(t(a)) and check if same results */
double time = cosmology_get_time_since_big_bang(&cosmo, a);
double my_a = cosmology_get_scale_factor_from_time(&cosmo, time);
double tmp = cosmology_get_time_since_big_bang(&cosmo, a);
tmp = cosmology_get_scale_factor(&cosmo, tmp);
/* check accuracy */
double rel_err = (my_a - a) / a;
message("Accuracy of %g at a=%g", rel_err, a);
assert(fabs(rel_err) < TOLERANCE);
tmp = (tmp - a) / a;
message("Accuracy of %g at a=%g", tmp, a);
assert(fabs(tmp) < TOLERANCE);
}
message("Everything seems fine with cosmology.");
......
tests/testIntegration.c deleted 100644 → 0
+ 0
− 173
View file @ b70c7ac4
/*******************************************************************************
* This file is part of SWIFT.
* Copyright (c) 2019 Matthieu Schaller (matthieu.schaller@durham.ac.uk)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
******************************************************************************/
#include "../config.h"
/* Some standard headers */
#include <fenv.h>
#include <math.h>
/* Local headers. */
#include "swift.h"
#ifdef HAVE_LIBGSL
#include <gsl/gsl_integration.h>
#endif
static INLINE double w_tilde(double a, double w0, double wa) {
return (a - 1.) * wa - (1. + w0 + wa) * log(a);
}
static INLINE double E(double Or, double Om, double Ok, double Ol, double w0,
double wa, double a) {
const double a_inv = 1. / a;
return sqrt(Or * a_inv * a_inv * a_inv * a_inv + Om * a_inv * a_inv * a_inv +
Ok * a_inv * a_inv + Ol * exp(3. * w_tilde(a, w0, wa)));
}
static INLINE double drift_integrand(double a, void *param) {
const struct cosmology *c = (const struct cosmology *)param;
const double Omega_r = c->Omega_r;
const double Omega_m = c->Omega_m;
const double Omega_k = c->Omega_k;
const double Omega_l = c->Omega_lambda;
const double w_0 = c->w_0;
const double w_a = c->w_a;
const double H0 = c->H0;
const double a_inv = 1. / a;
const double E_z = E(Omega_r, Omega_m, Omega_k, Omega_l, w_0, w_a, a);
const double H = H0 * E_z;
return (1. / H) * a_inv * a_inv * a_inv;
}
int main(int argc, char *argv[]) {
/* Initialize CPU frequency, this also starts time. */
unsigned long long cpufreq = 0;
clocks_set_cpufreq(cpufreq);
/* Choke on FP-exceptions */
#ifdef HAVE_FE_ENABLE_EXCEPT
feenableexcept(FE_DIVBYZERO | FE_INVALID | FE_OVERFLOW);
#endif
/* Fake parameter file with Planck+13 cosmology
* and the usual cosmological system of units */
struct swift_params *params =
(struct swift_params *)malloc(sizeof(struct swift_params));
parser_set_param(params, "InternalUnitSystem:UnitMass_in_cgs:1.98848e43");
parser_set_param(params,
"InternalUnitSystem:UnitLength_in_cgs:3.08567758e24");
parser_set_param(params, "InternalUnitSystem:UnitVelocity_in_cgs:1e5");
parser_set_param(params, "InternalUnitSystem:UnitCurrent_in_cgs:1.");
parser_set_param(params, "InternalUnitSystem:UnitTemp_in_cgs:1.");
parser_set_param(params, "Cosmology:Omega_m:0.307");
parser_set_param(params, "Cosmology:Omega_lambda:0.693");
parser_set_param(params, "Cosmology:Omega_b:0.0482519");
parser_set_param(params, "Cosmology:h:0.6777");
parser_set_param(params, "Cosmology:a_begin:0.0078125");
parser_set_param(params, "Cosmology:a_end:1.");
/* Initialise everything */
struct unit_system units;
units_init_from_params(&units, params, "InternalUnitSystem");
struct phys_const phys_const;
phys_const_init(&units, params, &phys_const);
struct cosmology cosmo;
cosmology_init(params, &units, &phys_const, &cosmo);
/* Initalise the GSL workspace */
size_t workspace_size = 100000;
gsl_integration_workspace *workspace =
gsl_integration_workspace_alloc(workspace_size);
gsl_function F = {&drift_integrand, &cosmo};
/* Loop over all the reasonable time-bins */
for (int bin = 6; bin < 24; ++bin) {
const int num_steps = (1LL << bin);
const integertime_t time_step_size = max_nr_timesteps / num_steps;
double min_err = 0.;
double max_err = 0.;
double sum_err = 0.;
integertime_t ti_min = 0;
integertime_t ti_max = 0;
message("Testing %d steps", num_steps);
/* Cycle through the time-steps */
for (integertime_t ti = 0; ti < max_nr_timesteps; ti += time_step_size) {
const integertime_t ti_beg = ti;
const integertime_t ti_end =
min(ti + time_step_size, max_nr_timesteps - 1);
const double a_beg = cosmology_get_scale_factor(&cosmo, ti_beg);
const double a_end = cosmology_get_scale_factor(&cosmo, ti_end);
/* Get the drift factor from SWIFT */
const double swift_drift_fac =
cosmology_get_drift_factor(&cosmo, ti, ti + time_step_size);
/* Get the exact drift factor */
double exact_drift_fac = 0., abserr;
gsl_integration_qag(&F, a_beg, a_end, 0, 1.0e-12, workspace_size,
GSL_INTEG_GAUSS61, workspace, &exact_drift_fac,
&abserr);
const double rel_err = 0.5 * (swift_drift_fac - exact_drift_fac) /
(swift_drift_fac + exact_drift_fac);
if (rel_err > max_err) {
max_err = rel_err;
ti_max = ti;
}
if (rel_err < min_err) {
min_err = rel_err;
ti_min = ti;
}
sum_err += fabs(rel_err);
}
message("Max error: %14e at a=[%.9f %.9f] ", max_err,
cosmology_get_scale_factor(&cosmo, ti_max),
cosmology_get_scale_factor(&cosmo, ti_max + time_step_size));
message("Min error: %14e at a=[%.9f %.9f]", min_err,
cosmology_get_scale_factor(&cosmo, ti_min),
cosmology_get_scale_factor(&cosmo, ti_min + time_step_size));
message("Sum error: %14e", sum_err);
message("Mean error: %14e", sum_err / num_steps);
if (max_err > 1e-4 || min_err < -1e-4)
error("Error too large to be acceptable");
}
#ifdef HAVE_LIBGSL
return 0;
#else
return 0;
#endif
}
tests/testOutputList.c
+ 1
− 16
View file @ 5d77c1ea
......@@ -19,10 +19,6 @@
******************************************************************************/
#include "../config.h"
/* Some standard headers */
#include <fenv.h>
#include <math.h>
/* Includes. */
#include "swift.h"
......@@ -90,8 +86,7 @@ void test_cosmo(struct engine *e, const char *name, const int with_assert) {
double output_time = 0;
/* Test Time */
e->time_base =
log(e->cosmology->a_end / e->cosmology->a_begin) / max_nr_timesteps;
e->time_base = log(e->time_end / e->cosmology->a_begin) / max_nr_timesteps;
e->ti_current = 0;
e->policy = engine_policy_cosmology;
......@@ -120,16 +115,6 @@ void test_cosmo(struct engine *e, const char *name, const int with_assert) {
};
int main(int argc, char *argv[]) {
/* Initialize CPU frequency, this also starts time. */
unsigned long long cpufreq = 0;
clocks_set_cpufreq(cpufreq);
/* Choke on FP-exceptions */
#ifdef HAVE_FE_ENABLE_EXCEPT
feenableexcept(FE_DIVBYZERO | FE_INVALID | FE_OVERFLOW);
#endif
/* Create a structure to read file into. */
struct swift_params params;
......
theory/Cosmology/coordinates.tex
+ 81
− 9
View file @ 5d77c1ea
\subsection{Choice of co-moving coordinates}
\label{ssec:ccordinates}
Note that, unlike the convention used by many codes, we do not express
quantities with ``little h'' ($h$) included; for instance units of
length are expressed in units of $\rm{Mpc}$ and not
${\rm{Mpc}}/h$. Similarly, the time integration operators (see
below)include an $h$-factor via the explicit appearance of
Note that, unlike the \gadget convention, we do not express quantities with
``little h'' ($h$) included; for instance units of length are expressed in
units of $\rm{Mpc}$ and not ${\rm{Mpc}}/h$. Similarly, the time integration
operators (see below) also include an $h$-factor via the explicit appearance of
the Hubble constant.\\
In physical coordinates, the Lagrangian for a particle $i$ in the
\cite{Springel2002} flavour of SPH with gravity reads
\begin{equation}
......@@ -63,8 +61,82 @@ codes\footnote{One additional inconvenience of our choice of
scale-factor. The signal velocity entering the time-step calculation
will hence read
$v_{\rm sig} = a\dot{\mathbf{r}'} + c = \frac{1}{a} \left(
|\mathbf{v}'| + a^{(5 - 3\gamma)/2}c'\right)$.}. For the
derivatives, this choice implies
$\dot{\mathbf{v}'} = 2H\mathbf{v}' + a^2\ddot{\mathbf{r}'}$.
|\mathbf{v}'| + a^{(5 - 3\gamma)/2}c'\right)$.}.
This choice implies that $\dot{\mathbf{v}'} = 2H\mathbf{v}' + a^2\ddot{\mathbf{r}'}$.
\subsubsection{SPH equations}
Using the SPH definition of density,
$\rho_i' = \sum_jm_jW(\mathbf{r}_{j}'-\mathbf{r}_{i}',h_i') =
\sum_jm_jW_{ij}'(h_i')$, we can follow \cite{Price2012} and apply the
Euler-Lagrange equations to write
\begin{alignat}{3}
\dot{\mathbf{r}}_i'&= \frac{1}{a^2} \mathbf{v}_i'& \label{eq:cosmo_eom_r} \\
\dot{\mathbf{v}}_i' &= -\sum_j m_j &&\left[\frac{1}{a^{3(\gamma-1)}}f_i'A_i'\rho_i'^{\gamma-2}\mathbf{\nabla}_i'W_{ij}'(h_i)\right. \nonumber\\
& && + \left. \frac{1}{a^{3(\gamma-1)}}f_j'A_j'\rho_j'^{\gamma-2}\mathbf{\nabla}_i'W_{ij}'(h_j)\right. \nonumber\\
& && + \left. \frac{1}{a}\mathbf{\nabla}_i'\phi'\right] \label{eq:cosmo_eom_v}
\end{alignat}
with
\begin{equation}
f_i' = \left[1 + \frac{h_i'}{3\rho_i'}\frac{\partial
\rho_i'}{\partial h_i'}\right]^{-1}, \qquad \mathbf{\nabla}_i'
\equiv \frac{\partial}{\partial \mathbf{r}_{i}'}. \nonumber
\end{equation}
These correspond to the equations of motion for density-entropy SPH
\citep[e.g. eq. 14 of][]{Hopkins2013} with cosmological and
gravitational terms. SPH flavours that evolve the internal energy $u$ instead of the
entropy require the additional equation of motion describing the evolution of
$u'$:
\begin{equation}
\dot{u}_i' = \frac{1}{a^2}\frac{P_i'}{\rho_i'^2} f_i'\sum_jm_j\left(\mathbf{v}_i' -
\mathbf{v}_j'\right)\cdot\mathbf{\nabla}_i'W_{ij}'(h_i).
\label{eq:cosmo_eom_u}
\end{equation}
In all these cases, the scale-factors appearing in the equations are
later absorbed in the time-integration operators
(Sec.~\ref{ssec:operators}) such that the RHS of the equations of
motions is identical for the primed quantities to the ones obtained in
the non-cosmological case for the physical quantities.
Additional terms in the SPH equations of motion (e.g. viscosity
switches) often rely on the velocity divergence and curl. Their SPH
estimators $\langle\cdot\rangle$ in physical coordinates can be
related to their estimators based on our primed-coordinates using:
\begin{align}
\left\langle \mathbf{\nabla}\cdot\dot{\mathbf{r}}_i \right\rangle &=
\frac{1}{a^2} \left\langle
\mathbf{\nabla}'\cdot\mathbf{v}_i'\right\rangle =
\frac{1}{a^2\rho_i'}\sum_j m_j\left(\mathbf{v}_j' -
\mathbf{v}_i'\right) \cdot \mathbf{\nabla}_i'W_{ij}'(h_i), \nonumber \\
\left\langle \mathbf{\nabla}\times\dot{\mathbf{r}}_i \right\rangle &=
\frac{1}{a^2} \left\langle
\mathbf{\nabla}'\times\mathbf{v}_i'\right\rangle =
\frac{1}{a^2\rho_i'}\sum_j m_j\left(\mathbf{v}_j' -
\mathbf{v}_i'\right) \times \mathbf{\nabla}_i'W_{ij}'(h_i). \nonumber
\end{align}
We finally give the expressions for the \cite{Monaghan1997} viscosity
term, that enters most SPH flavours, in our system of coordinates. The
viscosity ``tensor'' $\Pi_{ij} \equiv \frac{1}{2}\alpha_{\rm visc} v_{\rm
sig}'\mu_{ij}/\left(\rho_i + \rho_j\right)$ can be computed
in the primmed coordinates from the following quantities
\begin{align}
\omega_{ij}' &= \left(\mathbf{v}_i' - \mathbf{v}_j'\right) \cdot
\left(\mathbf{r}_i' - \mathbf{r}_j'\right), \\
\mu_{ij}' &=
a^{(3\gamma-5)/2} \left(\omega_{ij}' + a^2H\left|\mathbf{r}_i' -
\mathbf{r}_j'\right|^2 \right) / |\mathbf{r}_i' - \mathbf{r}_j' |,
\\
v_{\rm sig}' &= c_i' + c_j' - 3 \mu_{ij}'.
\end{align}
which leads to $\Pi_{ij}'=a^{3\gamma}\Pi_{ij}$. Note that he last quantity is
also used to compute the time-step size. The evolution of entropy is
then
\begin{equation}
\dot{A}_i = \dot{A}_i' = \frac{1}{a^2}\frac{1}{2}\frac{\gamma-1}{\rho_i'^{\gamma-1}} \sum_j
m_j \Pi_{ij}' \left(\mathbf{v}_i' -
\mathbf{v}_j'\right)\cdot\mathbf{\nabla}_i'W_{ij}'(h_i),
\end{equation}
indicating that the entropy evolves with the same scale-factor
dependence as the comoving positions (eq.~\ref{eq:cosmo_eom_r}).
theory/Cosmology/cosmology_standalone.tex
+ 3
− 5
View file @ 5d77c1ea
......@@ -26,7 +26,7 @@
\label{firstpage}
\begin{abstract}
Notes on the cosmology equations evolved in \swift
Making cosmology great again.
\end{abstract}
\begin{keywords}
......@@ -39,15 +39,13 @@ Notes on the cosmology equations evolved in \swift
\input{coordinates}
\input{sph}
\input{operators}
\input{timesteps}
%\input{artificialvisc}
\input{artificialvisc}
%\input{gizmo}
\input{gizmo}
\bibliographystyle{mnras}
\bibliography{./bibliography.bib}
......
theory/Cosmology/flrw.tex
+ 1
− 1
View file @ 5d77c1ea
......@@ -48,7 +48,7 @@ of $a_{\rm age}$ equally spaced between $\log(a_{\rm start})$ and $\log(a_{\rm
end})$. The values are obtained via adaptive quadrature using the 61-points
Gauss-Konrod rule implemented in the {\sc gsl} library \citep{GSL} with a
relative error limit of $\epsilon=10^{-10}$. The value for a specific $a$ (over
the course of a simulation run) is then obtained by cubic interpolation of the
the course of a simulation run) is then obtained by linear interpolation of the
table.
\subsubsection{Additional quantities}
......
theory/Cosmology/operators.tex
+ 6
− 7
View file @ 5d77c1ea
......@@ -47,12 +47,11 @@ and the corresponding change in redshift:
\Delta z &= \frac{1}{a_n} - \frac{1}{a_{n+1}} \approx -\frac{H}{a} \Delta t_{\rm cosmic}.
\end{align}
Following the same method as for the age of the Universe
(sec. \ref{ssec:flrw}), these three non-trivial integrals are evaluated
numerically at the start of the simulation for a series $10^4$ values of
$a$ placed at regular intervals between $\log a_{\rm begin}$ and
$\log a_{\rm end}$. The values for a specific pair of scale-factors $a_n$
and $a_{n+1}$ are then obtained by interpolating that table with a cubic
polynomial. An accuracy better than one part in $10^8$ is achieved for all
reasonable cosmologies and time-step lengths.
(sec. \ref{ssec:flrw}), these three non-trivial integrals are
evaluated numerically at the start of the simulation for a series
$10^4$ values of $a$ placed at regular intervals between $\log a_{\rm
begin}$ and $\log a_{\rm end}$. The values for a specific pair of
scale-factors $a_n$ and $a_{n+1}$ are then obtained by interpolating
that table linearly.
theory/Cosmology/sph.tex deleted 100644 → 0
+ 0
− 75
View file @ b70c7ac4
\subsubsection{SPH equations}
Using the SPH definition of density,
$\rho_i' = \sum_jm_jW(\mathbf{r}_{j}'-\mathbf{r}_{i}',h_i') =
\sum_jm_jW_{ij}'(h_i')$, we can follow \cite{Price2012} and apply the
Euler-Lagrange equations to write
\begin{alignat}{3}
\dot{\mathbf{r}}_i'&= \frac{1}{a^2} \mathbf{v}_i'& \label{eq:cosmo_eom_r} \\
\dot{\mathbf{v}}_i' &= -\sum_j m_j &&\left[\frac{1}{a^{3(\gamma-1)}}f_i'A_i'\rho_i'^{\gamma-2}\mathbf{\nabla}_i'W_{ij}'(h_i)\right. \nonumber\\
& && + \left. \frac{1}{a^{3(\gamma-1)}}f_j'A_j'\rho_j'^{\gamma-2}\mathbf{\nabla}_i'W_{ij}'(h_j)\right. \nonumber\\
& && + \left. \frac{1}{a}\mathbf{\nabla}_i'\phi'\right] \label{eq:cosmo_eom_v}
\end{alignat}
with
\begin{equation}
f_i' = \left[1 + \frac{h_i'}{3\rho_i'}\frac{\partial
\rho_i'}{\partial h_i'}\right]^{-1}, \qquad \mathbf{\nabla}_i'
\equiv \frac{\partial}{\partial \mathbf{r}_{i}'}. \nonumber
\end{equation}
These correspond to the equations of motion for density-entropy SPH
\citep[e.g. eq. 14 of][]{Hopkins2013} with cosmological and
gravitational terms. SPH flavours that evolve the internal energy $u$ instead of the
entropy require the additional equation of motion describing the evolution of
$u'$:
\begin{equation}
\dot{u}_i' = \frac{1}{a^2}\frac{P_i'}{\rho_i'^2} f_i'\sum_jm_j\left(\mathbf{v}_i' -
\mathbf{v}_j'\right)\cdot\mathbf{\nabla}_i'W_{ij}'(h_i).
\label{eq:cosmo_eom_u}
\end{equation}
In all these cases, the scale-factors appearing as the first term on
the RHS of the equations are later absorbed in the time-integration
operators (Sec.~\ref{ssec:operators}) such that the RHS of the
equations of motions is identical for the primed quantities to the
ones obtained in the non-cosmological case for the physical
quantities.
Additional terms in the SPH equations of motion (e.g. viscosity
switches) often rely on the velocity divergence and curl. Their SPH
estimators $\langle\cdot\rangle$ in physical coordinates can be
related to their estimators based on our primed-coordinates using:
\begin{align}
\left\langle \mathbf{\nabla}\cdot\dot{\mathbf{r}}_i \right\rangle &=
\frac{1}{a^2} \left\langle
\mathbf{\nabla}'\cdot\mathbf{v}_i'\right\rangle =
\frac{1}{a^2\rho_i'}\sum_j m_j\left(\mathbf{v}_j' -
\mathbf{v}_i'\right) \cdot \mathbf{\nabla}_i'W_{ij}'(h_i), \nonumber \\
\left\langle \mathbf{\nabla}\times\dot{\mathbf{r}}_i \right\rangle &=
\frac{1}{a^2} \left\langle
\mathbf{\nabla}'\times\mathbf{v}_i'\right\rangle =
\frac{1}{a^2\rho_i'}\sum_j m_j\left(\mathbf{v}_j' -
\mathbf{v}_i'\right) \times \mathbf{\nabla}_i'W_{ij}'(h_i). \nonumber
\end{align}
We finally give the expressions for the \cite{Monaghan1997} viscosity
term, that enters most SPH flavours, in our system of coordinates. The
viscosity ``tensor'' $\Pi_{ij} \equiv \frac{1}{2}\alpha_{\rm visc} v_{\rm
sig}'\mu_{ij}/\left(\rho_i + \rho_j\right)$ can be computed
in the primmed coordinates from the following quantities
\begin{align}
\omega_{ij}' &= \left(\mathbf{v}_i' - \mathbf{v}_j'\right) \cdot
\left(\mathbf{r}_i' - \mathbf{r}_j'\right), \\
\mu_{ij}' &=
a^{(3\gamma-5)/2} \left(\omega_{ij}' + a^2H\left|\mathbf{r}_i' -
\mathbf{r}_j'\right|^2 \right) / |\mathbf{r}_i' - \mathbf{r}_j' |,
\\
v_{\rm sig}' &= c_i' + c_j' - 3 \mu_{ij}'.
\end{align}
which leads to $\Pi_{ij}'=a^{3\gamma}\Pi_{ij}$. Note that he last quantity is
also used to compute the time-step size. The evolution of entropy is
then
\begin{equation}
\dot{A}_i = \dot{A}_i' = \frac{1}{a^2}\frac{1}{2}\frac{\gamma-1}{\rho_i'^{\gamma-1}} \sum_j
m_j \Pi_{ij}' \left(\mathbf{v}_i' -
\mathbf{v}_j'\right)\cdot\mathbf{\nabla}_i'W_{ij}'(h_i),
\end{equation}
indicating that the entropy evolves with the same scale-factor
dependence as the comoving positions (eq.~\ref{eq:cosmo_eom_r}).
theory/Cosmology/timesteps.tex
+ 0
− 2
View file @ 5d77c1ea
......@@ -44,5 +44,3 @@ dominates the overall time-step size calculation.
\int_{a_n}^{a_{n+1}} H dt = \int_{a_n}^{a_{n+1}} \frac{da}{a} =
\log{a_{n+1}} - \log{a_n}.
\end{equation}
\subsubsection{Maximal time-step size}
\ No newline at end of file
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